Thursday, March 27, 2008

Emergence of Tetracycline-Resistant Vibrio cholerae O1 Serotype Inaba, in Kolkata, India.

Emergence of Tetracycline-Resistant Vibrio cholerae O1 Serotype Inaba, in Kolkata, India.

Jpn J Infect Dis. 2008 Mar

Roychowdhury A, Pan A, Dutta D, Mukhopadhyay AK, Ramamurthy T, Nandy RK, Bhattacharya SK, Bhattacharya MK.
National Institute of Cholera and Enteric Diseases, Kolkata, India.

Out of 2,235 diarrheal stool samples collected from patients admitted to the Infectious Diseases Hospital, Kolkata, 343 cases were positive for Vibrio cholerae (341, V. cholerae O1 and 2, O139). During the year 2004, infections caused by V. cholerae serotype Ogawa and Inaba were 93 and 7%, respectively, while in 2005, the Inaba isolation rate rose to 88% as compared to 12% for Ogawa. Susceptibility to antimicrobial agents revealed that the O1 strains were resistant to multiple antibiotics (ampicillin, co-trimoxazole, furazolidone, nalidixic acid and streptomycin) with reduced susceptibility to ciprofloxacin. Increased isolation of tetracycline-resistant strains (27.3% for Ogawa and 15% for Inaba) was noted in 2005. It appears that the population might be at risk of infection by the Inaba serotype and that tetracycline may not be useful for the treatment.

Japanese Journal of Infectious Disease

Emergence of Vibrio cholerae O1 biotype El Tor serotype Inaba causing outbreaks of cholera in Orissa, India.

Jpn J Infect Dis. 2006 Aug

Pal BB, Khuntia HK, Samal SK, Das SS, Chhotray GP.
Pathology and Microbiology Division, Regional Medical Research Centre, Orissa, India.

A total of 431 rectal swabs, collected from acute diarrheal cases at a surveillance site and at different diarrheal outbreak areas of Orissa from May to October 2005, were bacteriologically analyzed. Out of 265 culture-positive samples, Vibrio cholerae O1 was isolated in 56 samples (20.8%), of which 37 were the Inaba serotype and 19 were the Ogawa. The antibiogram profile revealed that all the V. cholerae O1 Ogawa and Inaba serotypes were uniformly sensitive to ampicillin, chloramphenicol, gentamicin, ciprofloxacin, norfloxacin and tetracycline. The V. cholerae O1 Inaba serotypes were resistant to furazolidone and nalidixic acid, while the Ogawa strains were resistant to furazolidone, nalidixic acid and neomycin. The multiplex polymerase chain reaction (PCR) assay on some selected strains of both serotypes revealed that all the strains were positive for ctxA and tcpA genes showing biotype El Tor. The present study revealed the emergence of V. cholerae O1 biotype El Tor serotype Inaba, which caused sporadic outbreaks of cholera in 2005. The outbreaks of diarrheal disorders in one geographical area of the state (in the Pattamundai area, Kendrapara district) in 2005 were due to V. cholerae O1 Ogawa, whereas the other outbreaks in other areas (Puri, Khurda and Dhenkanal districts) from August to October 2005 were due to V. cholerae O1 serotype Inaba. This is the first report that an emergence of V. cholerae O1 serotype Inaba caused sporadic outbreaks of cholera in different parts of Orissa. Switching over of V. cholerae O1 Ogawa strains to Inaba, causing diarrheal outbreaks in Orissa, needs close monitoring.

Japanese Journal of Infectious Disease

Sunday, March 23, 2008

Antibiotics for adults with clinically diagnosed acute rhinosinusitis: a meta-analysis of individual patient data.

Antibiotics for adults with clinically diagnosed acute rhinosinusitis: a meta-analysis of individual patient data.

Lancet. 2008 Mar

Young J, De Sutter A, Merenstein D, van Essen GA, Kaiser L, Varonen H, Williamson I, Bucher HC.

Correspondence to: Jim Young, Basel Institute for Clinical Epidemiology, Hebelstrasse 10, University Hospital Basel, CH-4031 Basel, Switzerland

Basel Institute for Clinical Epidemiology, University Hospital Basel, Basel, Switzerland.

BACKGROUND: Primary-care physicians continue to overprescribe antibiotics for acute rhinosinusitis because distinction between viral and bacterial sinus infection is difficult. We undertook a meta-analysis of randomised trials based on individual patients' data to assess whether common signs and symptoms can be used to identify a subgroup of patients who benefit from antibiotics.

METHODS: We identified suitable trials--in which adult patients with rhinosinusitis-like complaints were randomly assigned to treatment with an antibiotic or a placebo--by searching the Cochrane Central Register of Controlled Trials, Medline, and Embase, and reference lists of reports describing such trials. Individual patients' data from 2547 adults in nine trials were checked and re-analysed. We assessed the overall effect of antibiotic treatment and the prognostic value of common signs and symptoms by the number needed to treat (NNT) with antibiotics to cure one additional patient.

FINDINGS: 15 patients with rhinosinusitis-like complaints would have to be given antibiotics before an additional patient was cured (95% CI NNT[benefit] 7 to NNT[harm] 190). Patients with purulent discharge in the pharynx took longer to cure than those without this sign; the NNT was 8 patients with this sign before one additional patient was cured (95% CI NNT[benefit] 4 to NNT[harm] 47). Patients who were older, reported symptoms for longer, or reported more severe symptoms also took longer to cure but were no more likely to benefit from antibiotics than other patients.

INTERPRETATION: Common clinical signs and symptoms cannot identify patients with rhinosinusitis for whom treatment is clearly justified. Antibiotics are not justified even if a patient reports symptoms for longer than 7-10 days.

The Lancet

Antibiotic treatment for Clostridium difficile-associated diarrhea in adults

Antibiotic treatment for Clostridium difficile-associated diarrhea in adults

Cochrane Database Syst Rev. 2007 Jul

Nelson R.
Northern General Hospital, Department of General Surgery, Herries Road, Sheffield, Yorkshire, UK, S5 7AU.

BACKGROUND: Clostridium difficile (C. difficile) is recognized as a frequent cause of antibiotic-associated diarrhea and colitis.

OBJECTIVES: The aim of this review is to establish the efficacy of antibiotic therapy for C. difficile-associated diarrhea (CDAD), to identify the most effective antibiotic treatment for CDAD in adults and to determine the need for stopping the causative antibiotic during therapy.

SEARCH STRATEGY: MEDLINE (1966 to 2006), EMBASE (1980 to 2006), Cochrane Central Database of Controlled Trials and the Cochrane IBD Review Group Specialized Trials Register were searched using the following search terms: "pseudomembranous colitis and randomized trial"; "Clostridium difficile and randomized trial"; "antibiotic associated diarrhea and randomized trial".

SELECTION CRITERIA: Only randomized, controlled trials assessing antibiotic treatment for CDAD were included in the review. Probiotic trials are excluded. The following outcomes were sought: initial resolution of diarrhea; initial conversion of stool to C. difficile cytotoxin and/or stool culture negative; recurrence of diarrhea; recurrence of fecal C. difficile cytotoxin and/or positive stool culture; patient response to cessation of prior antibiotic therapy; sepsis; emergent surgery: fecal diversion or colectomy; and death.

DATA COLLECTION AND ANALYSIS: Data were analyzed using the MetaView statistical package in Review Manager. For dichotomous outcomes, relative risks (RR) and 95% confidence intervals (CI) were derived from each study. When appropriate, the results of included studies were combined for each outcome. For dichotomous outcomes, pooled RR and 95% CI were calculated using a fixed effect model, except where significant heterogeneity was detected, at which time the random effects model was used. Data heterogeneity was calculated using MetaView.

MAIN RESULTS: Twelve studies (total of 1157 participants) involving patients with diarrhea who recently received antibiotics for an infection other than C. difficile were included. The definition of diarrhea ranged from at least two loose stools per day with an associated symptom such as rectal temperature > 38 (o)C, to at least six loose stools in 36 hours. Eight different antibiotics were investigated: vancomycin, metronidazole, fusidic acid, nitazoxanide, teicoplanin, rifampin, rifaximin and bacitracin. In paired comparisons, no single antibiotic was clearly superior to others, though teicoplanin, an antibiotic of limited availability and great cost, showed in some outcomes significant benefit over vancomycin and fusidic acid, and a trend towards benefit compared to metronidazole. Only one placebo controlled trial was done and no conclusions can be drawn from it due to small size and classification error. Only one study investigated synergistic antibiotic combination, metronidazole and rifampin, and there was no advantage to the drug combination.

AUTHORS' CONCLUSIONS: Current evidence leads to uncertainty whether mild CDAD needs to be treated. Patients with mild CDAD may resolve their symptoms as quickly without treatment. The only placebo-controlled study shows vancomycin's superior efficacy. However, this result should be treated with caution due to the small number of patients enrolled and the poor methodological quality of the trial. The Johnson study of asymptomatic carriers also shows that placebo is better than vancomycin or metronidazole for eliminating C. difficile in stool during follow-up. If one does decide to treat, then two goals of therapy need to be kept in mind: improvement of the patient's clinical condition and prevention of spread of C. difficile infection to other patients. Given these two considerations, one should choose the antibiotic that brings both symptomatic cure and bacteriologic cure.

In this regard, teicoplanin appears to be the best choice because the available evidence suggests that it is better than vancomycin for bacteriologic cure and has borderline superior effectiveness in terms of symptomatic cure. Teicoplanin is not readily available in the United States, which must be taken into account when making treatment decisions in that country.

Plain language summary

Antibiotic therapy for Clostridium difficile-associated diarrhea (CDAD) needs further investigation.Diarrhea may be a side effect of many commonly used antibiotics, and this is in some cases due to overgrowth of a bacterium called Clostridium difficile (C. difficile) in the colon after other bacteria have been killed. The seriousness of C. difficile-associated diarrhea can range from being a nuisance to a life threatening or even fatal disease. The treatment of CDAD is usually cessation of the initiating antibiotic and immediate administration of a new antibiotic. However each of these three strategies, cessation of the original antibiotic, immediate retreatment, and the choice of a new antibiotic are poorly supported by currently available evidence. The antibiotic that is most tested, vancomycin, is the one most prone to serious side effects. Seven other antibiotics are included in this review and within the limitations of the included studies, they each seem to be as effective as vancomycin.

The Cochrane Library

Thursday, March 20, 2008

Pediatric fingertip injuries: do prophylactic antibiotics alter infection rates?

Pediatric fingertip injuries: do prophylactic antibiotics alter infection rates?

Pediatr Emerg Care. 2008 Mar

Altergott C, Garcia FJ, Nager AL.
Department of Pediatrics, Division of Emergency Medicine, Childrens Hospital Los Angeles, University of Southern California Keck School of Medicine, Los Angeles, CA 90027, USA.

STUDY OBJECTIVE: Fingertip injuries are common in the pediatric population. Considerable controversy exists as to whether prophylactic antibiotics are necessary after repair of these injuries. Our goal was to compare the rate of bacterial infections among subgroups treated with and without prophylactic antibiotics. The study hypothesis was that infection rates were similar in the 2 groups.

METHODS: This was a prospective randomized control trial of pediatric patients presenting to an urban children's hospital with trauma to the distal fingertip, requiring repair. Patients were randomized to 2 groups: group 1 received no antibiotics, and group 2 received antibiotics (cephalexin). Repairs were performed in a standardized fashion, and all patients were reevaluated in the same emergency department in 48 hours and again by phone 7 days after repair. The primary outcome measure was the rate of infection at 7 days after repair.

RESULTS: One hundred forty-six patients were initially enrolled in the study, 11 patients were withdrawn before study completion, 69 subjects were randomized to the no-antibiotic group, and 66 subjects were randomized to the antibiotic group. There was 1 infection in each group at 7 days after repair. The infection rate was 1.45% (95% confidence interval, 0.04%-7.81%) for the no-antibiotic group and was 1.52% (95% confidence interval, 0.04%-8.16%) for the antibiotic group, not statistically significant (P = 1.00).

CONCLUSIONS: This study suggests that routine prophylactic antibiotics do not reduce the rate of infection after repair of distal fingertip injuries.

Lippincott, Williams & Wilkins

Friday, March 14, 2008

Trends in Resistance to Ciprofloxacin, Cefazolin, and Gentamicin in the Treatment of Bacterial Keratitis

Trends in Resistance to Ciprofloxacin, Cefazolin, and Gentamicin in the Treatment of Bacterial Keratitis

J Ocul Pharmacol Ther. 2008 Mar 10

Afshari NA, Ma JJ, Duncan SM, Pineda R, Starr CE, Decroos FC, Johnson CS, Adelman RA.
Duke University Eye Center, Duke University Medical Center, Durham, NC.

Purpose: The aim of this study was to evaluate the microbial profile, resistance patterns, and antibiotic sensitivity of bacterial keratitis to three commonly used ocular antibiotics.

Methods: All cases of bacterial keratitis referred to the Massachusetts Eye and Ear Infirmary Microbiology Laboratory from two consecutive annual 10-month periods were reviewed. The bacterial profile and resistance to ciprofloxacin, cefazolin, and gentamicin was evaluated within the two intervals.

Results: Of the 485 cultures analyzed, 66.4% (322) were positive for bacterial isolates. Of these, 19.2% were polymicrobial, 87.5% were gram-positive, and 12.5% were gram-negative. The most prevalent isolate was coagulase-negative Staphylococcus (45.5%), followed by S. aureus (15.2%).

The resistance patterns for gram-positive bacteria for ciprofloxacin for the first versus second time interval were 12% and 22% (P = 0.04) respectively, for cefazolin 13% and 23% (P = 0.04), and for gentamicin 4% and 7% (P = 0.36). The resistance patterns for gram-negative bacteria for ciprofloxacin, cefazolin, and gentamicin were not significantly different in the two tested time periods (all P greater then 0.05).

Conclusions: There was increased resistance of gram-positive organisms to ciprofloxacin and cefazolin, but not gentamicin, in the two examined time periods. Increased resistance to these commonly used antibiotics emphasizes the need for close follow-up after initial empiric treatment, and maintaining a low threshold for selecting alternative therapy.


Thursday, March 06, 2008

Ciprofloxacin in primary prophylaxis of spontaneous bacterial peritonitis: A randomized, placebo-controlled study.

Ciprofloxacin in primary prophylaxis of spontaneous bacterial peritonitis: A randomized, placebo-controlled study.

J Hepatol. 2008 Feb

Terg R, Fassio E, Guevara M, Cartier M, Longo C, Lucero R, Landeira C, Romero G, Dominguez N, Muñoz A, Levi D, Miguez C, Abecasis R.
Unidad de Hígado, Hospital de Gastroenterología “Dr. Bonorino Udaondo”, Sección Hepatología, Av. Caseros 2061, 1264 Buenos Aires, Argentina.

BACKGROUND/AIMS: Low protein concentration in ascitic fluid has been identified as a risk factor for spontaneous bacterial peritonitis (SBP). Until now, primary prophylaxis has not been recommended in these patients. The aim was to investigate the efficacy of long-term administration of ciprofloxacin to prevent SBP.

METHODS: One hundred cirrhotic patients with (less then) 1.5g/dl of total protein in ascitic fluid were randomized prospectively, in a double blind fashion to receive ciprofloxacin 500mg/day (n=50) or placebo (n=50) for 12 months.

RESULTS: Baseline data were similar in both groups. In the ciprofloxacin group, SBP occurred almost four times less frequently than in the placebo group but it was not statistically significant. The probability of survival at 12 months was significantly higher in patients receiving ciprofloxacin (86% versus 66%) (p<0.04). p="0.05).">

CONCLUSIONS: Patients with cirrhosis and low protein concentration in ascitic fluid are candidates to receive long-term prophylaxis to reduce the risk of infections and improve survival.


Wednesday, March 05, 2008

New British and American guidelines for the antibiotic prophylaxis of infective endocarditis: do the changes make sense? A critical review.

New British and American guidelines for the antibiotic prophylaxis of infective endocarditis: do the changes make sense? A critical review.

Curr Opin Infect Dis. 2008 Apr

Shanson D.
Department of Medical Microbiology, Great Ormond Street Hospital for Children, London, UK.

PURPOSE OF REVIEW: The British Society for Antimicrobial Chemotherapy and the American Heart Association have radically revised their guidelines for the antibiotic prophylaxis of endocarditis. This review discusses the evidence behind the most controversial changes and considers possible future developments.

RECENT FINDINGS: The new guidelines emphasize good oral hygiene for preventing viridans streptococcal endocarditis. Antibiotic prophylaxis for dental procedures is only recommended for patients with the highest-risk cardiac conditions. American Heart Association guidelines no longer recommend prophylaxis for urological and gastrointestinal procedures.

SUMMARY: While only up to 6% of endocarditis cases may be prevented by antibiotic prophylaxis there is controversy as to what to recommend for the individual cardiac patient undergoing a given procedure. The new guidelines about dental prophylaxis are based on epidemiological studies that failed to include sufficient subjects undergoing specific interventions. When considering viridans streptococcal rather than total bacteraemia rates, asserting that the prevalence of bacteraemia after invasive dental procedures is similar to that after toothbrushing may be incorrect. The British Society for Antimicrobial Chemotherapy report probably overestimates the risk of fatal anaphylaxis after an oral dose of amoxicillin. In contrast, the American Heart Association guidelines comment on the absence of any reports of fatal anaphylaxis associated with the antibiotic prophylaxis of endocarditis.

Lippincott, Williams & Wilkins

Sunday, March 02, 2008

Ciprofloxacin-Resistant Salmonella enterica Serotype Typhimurium, China

Ciprofloxacin-Resistant Salmonella enterica Serotype Typhimurium, China

EID -Volume 14, Number 3–March 2008

Ciprofloxacin-Resistant Salmonella enterica Serotype Typhimurium, China
Shenghui Cui,* Jingyun Li,* Ziyong Sun,† Changqin Hu,* Shaohong Jin,* Yunchang Guo,‡ Lu Ran,‡ and Yue Ma*
*State Food and Drug Administration, Beijing, People's Republic of China; †Huazhong University of Science and Technology, Wuhan, People's Republic of China; and ‡Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
Salmonellae are a common cause of community-acquired foodborne bacterial gastroenteritis worldwide. The incidence of Salmonella infections in the People's Republic of China has not been well documented. However, in the United States, ≈1.4 million persons are infected by Salmonella spp. each year (
1). Although >2,500 serotypes have been reported, Salmonella enterica serotype Typhimurium is 1 of the leading serotypes causing salmonellosis worldwide (2). Fluoroquinolones such as ciprofloxacin are strongly recommended for treatment of severe S. Typhimurium infections in adults (3).

In this study, we characterized all S. Typhimurium isolates recovered from May 2002 through October 2005 from outpatients of Tongji Hospital, Wuhan, China, a sentinel hospital in the National Center for Surveillance of Antimicrobial Resistance. During the time of this study, Tongji Hospital strictly followed the recommendation for treatment of severe S. Typhimurium infections.

The Study

We analyzed stool samples from outpatients who came to Tongji Hospital from the local community for treatment of diarrhea during the study period. A total of 44 S. Typhimurium isolates were recovered from the samples. S. Typhimurium was identified by using standard biochemical tests and commercial typing antiserum (Statens Serum Institute, Copenhagen, Denmark) according to the manufacturer's instructions. MICs of 15 antimicrobial drugs (
Table) were determined by using the broth-microdilution method; susceptibility to streptomycin was measured by using the disk-diffusion method as recommended by the Clinical and Laboratory Standards Institute (4). All isolates were further characterized by mutation analysis in the quinolone-resistance determining regions (QRDRs), pulsed-field gel electrophoresis (PFGE), and screening for class I integrons and β-lactamase genes as previously described (5–8).

Of the 44 isolates, 36 (82%) were resistant to nalidixic acid and 31 (70%) were resistant to ciprofloxacin (
Table). Only 3 isolates, recovered in 2002, were susceptible to all 15 tested antimicrobial drugs; 36 (82%) displayed resistance to at least 8 drugs. Of 13 antimicrobial drug–resistant phenotypes identified, the most often observed phenotype (21/44) was resistance to amoxicillin–clavulanic acid, ampicillin, chloramphenicol, ciprofloxacin, gentamicin, nalidixic acid, sulfamethoxazole, streptomycin, trimethoprim–sulfamethoxazole, and tetracycline (R-type AcAmCCpGNSStSxtT). All isolates were susceptible to cefotaxime and ceftazidime; 5 isolates obtained in 2004 were intermediately susceptible to cefepime (MIC 16 μg/mL) (Appendix Figure).

Overall, 8 PFGE strain types (A–H) and 6 clusters (1–6) were identified. All isolates that belonged to clusters 1, 2, and 4 were resistant to ciprofloxacin and to 8–11 other antimicrobial drugs. Two dominant patterns, B and F, were identified and included 16 and 10 ciprofloxacin-resistant isolates, respectively. Among 16 isolates of pattern B, 14 isolates showed the R-type AcAmCCpGNSStSxtT, and 1 was additionally resistant to kanamycin. In pattern F, 4 isolates showed the R-type AcAmCCpGNSStSxtT, and 5 were additionally resistant to kanamycin.

Point mutations in the QRDR of gyrA, parC, or parE were identified in 35 of 36 nalidixic acid–resistant isolates, whereas no gyrB mutations and no qnr plasmid were found. For 5 nalidixic acid–resistant and ciprofloxacin low-level–resistant isolates, 4 isolates harbored single (D87N) or double (S83F, D87N) mutations in GyrA, and no mutation was found in 1 isolate (ST6). All 31 ciprofloxacin-resistant isolates accumulated a minimum of 3 mutations: GyrA(S83F, D87N), ParC(S80R) (28 isolates) or GyrA(S83F, D87G), ParC(S80R) (3 isolates). Two ciprofloxacin-resistant isolates with PFGE pattern C and 1 isolate with PFGE pattern A2 harbored an additional mutation in ParE (S458P)

Of 39 sulfamethoxazole-resistant isolates encompassing PFGE clusters 1, 2, 3, and 4, 37 possessed class 1 integrons. All class 1 integron–positive isolates were resistant to 6–12 antimicrobial drugs; 2 distinct class 1 integrons were identified in 37 isolates. Of isolates obtained from 2002 through 2005, 32 contained a 1.9-kb integron gene cassette dhfrXII-orfF-aadA2. In 2004 and 2005, 3 and 2 isolates, respectively, contained a 2-kb integron gene cassette blaOXA-30-aadA1. None of the 36 ampicillin-resistant isolates contained TEM or SHV enzyme, but OXA-30 gene was detected in 32 isolates, identical in DNA sequence to GenBank AF255921. All 32 isolates harboring OXA-30 enzyme showed MICs to cefepime of 2–16 μg/mL, whereas isolates lacking OXA-30 showed MICs to cefepime of <1>.


We report a high incidence of fluoroquinolone-resistant S. Typhimurium isolates from Tongji Hospital outpatients. The MIC variation for ciprofloxacin differed 2- to 4-fold in isolates that had the same QRDR mutation profile, which implies that other mechanisms might partially contribute to the resistance phenotype (
Appendix Figure).

After PFGE analysis, S. Typhimurium isolates were grouped into 3 ciprofloxacin-susceptible clusters and ciprofloxacin-resistant clusters. Similar distribution patterns have also been observed in isolates from Japan (
9), which suggests a distinct genetic lineage for ciprofloxacin-resistant isolates that have become dominant. Studies have reported that ciprofloxacin-resistant S. Typhimurium isolates were usually resistant to multiple drugs (9,10). In this study, all ciprofloxacin-resistant S. Typhimurium isolates were resistant to 8–11 additional antimicrobial drugs. Among the 32 isolates harboring OXA-30 enzyme in this study, only 5 with PFGE pattern F showed intermediate resistance to cefepime, which suggests different levels of OXA gene expression or the contribution of other unknown mechanisms.

The high incidence of quinonlone-resistant S. Typhimurium isolates in this study might be affected by several factors. First, patients infected by antimicrobial drug–resistant S. Typhimurium strains had higher rates of hospitalization than did patients infected by susceptible strains (
11,12), and the isolates in this study were from a university-affiliated medical center that usually treats patients with severe illness. Second, US studies have estimated that half of outpatient antimicrobial drugs were inappropriately prescribed for conditions such as viral illness (13). In China, inappropriate prescriptions might be even more common because antimicrobial drug prescriptions in hospitals are a source of profit. Although we do not have patient antimicrobial drug–use information, the easy access to antimicrobial drugs raises the possibility that outpatients might have taken fluoroquinolones after the onset of the illness but before the collection of stool specimens. Third, because livestock products are a common source of salmonellosis, the dissemination of ciprofloxacin-resistant S. Typhimurium might have been facilitated by the use of fluoroquinolones in livestock production (2). Last, use of other antimicrobial drugs, such as ampicillin, gentamicin, or streptomycin, may also contribute to the spreading of fluoroquinolone-resistant S. Typhimurium because all the ciprofloxacin-resistant isolates were also resistant to 8–11 additional antimicrobial drugs.

Although fluoroquinolone-resistant isolates were prevalent in Tongji Hospital, ciprofloxacin is still empirically used to treat salmonellosis in adults, due partly to the absence of systematic surveillance programs to actively monitor antimicrobial drug resistance in Salmonella spp. Because local data on antimicrobial drug susceptibility are less available, we strongly recommend that hospitals and national and local health laboratories develop and maintain the capacity to perform Salmonella culture and in vitro susceptibility testing.


We thank Patrick F. McDermott for revision and helpful comments on the manuscript.

This research was supported by grant (2005DIB3J159) from the Ministry of Science and Technology of the People's Republic of China.

Dr Cui is a microbiologist in the National Center for Surveillance of Antimicrobial Resistance, the State Food and Drug Administration, Beijing, China. His professional interests include developing detection methods for bacterial pathogens, molecular epidemiology, and antimicrobial drug–resistance mechanisms of bacterial pathogens.


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Saturday, March 01, 2008

Intracameral antibiotics: Questions for the United States based on prospective studies

Intracameral antibiotics: Questions for the United States based on prospective studies

J Cataract Refract Surg. 2008 Mar

Liesegang TJ.
From the Mayo Clinic, Jacksonville, Florida, USA.

Recent prospective studies from Europe suggest the use of intracameral antibiotics for prophylaxis of endophthalmitis, although the studies did not make a comparison with the most common United States prophylaxis techniques. Thus, the European studies as well as the present literature were reviewed in an attempt to place the European studies in perspective with regard to the present U.S. protocol and the available literature. There is no worldwide-established approach to prophylaxis of endophthalmitis. In the absence of a strong evidence-based approach most surgeons use surrogate studies to support their techniques and mold their opinions based on their interpretation of the literature and when they believe organisms causing endophthalmitis enter the eye. The review showed that preoperative topical antibiotics limit the number of bacteria on the ocular surface at surgery and postoperative topical antibiotics are most appropriate to address postoperative inoculation until the wound is sealed (with no tapering). Whereas intracameral antibiotic injection may be an appropriate route of administration to address inoculation occurring at the time of surgery, more research on safety and effectiveness is needed before we expose the millions of eyes having cataract surgery each year. A multipronged approach to limit endophthalmitis risk is also needed, with antibiotics as only part of the strategy.


Antimicrobials as a contributory factor in oral candidosis - a brief overview

Antimicrobials as a contributory factor in oral candidosis - a brief overview

Oral Dis. 2008 Mar

Soysa NS, Samaranayake LP, Ellepola AN.
Division of Pharmacology, Department of Oral Medicine and Periodontology, Faculty of Dental Sciences, University of Peradeniya, Peradeniya, Sri Lanka; 2Oral Bio-Sciences, Faculty of Dentistry, University of Hong Kong, Hong Kong; 3Department of Bioclinical Sciences, Faculty of Dentistry, Health Sciences Center, Kuwait University, Kuwait

Dr NS Soysa, Division of Pharmacology, Department of Oral Medicine and Periodontology, Faculty of Dental Sciences, University of Peradeniya, Peradeniya, Sri Lanka. Tel: 94-81-2387500, Fax: 94-81-2388948, E-mail:

The advent of the human immunodeficiency virus infection and the increasing prevalence of compromised individuals in the community due to modern therapeutic advances have resulted in a resurgence of opportunistic infections, including oral candidosis, which is by far the most common oral fungal infection in man. Broad-spectrum antibiotics used in the treatment of a wide range of disease conditions have also been attributed as a predisposing factor of oral candidosis. In this mini review we discuss the research findings on the relationship between antibiotics and oral candidosis and possible mechanisms of pathogenicity following such therapy.

Blackwell Synergy

Effect and Mechanism of Andrographolide on the Recovery of Pseudomonas aeruginosa Susceptibility to Several Antibiotics

Effect and Mechanism of Andrographolide on the Recovery of Pseudomonas aeruginosa Susceptibility to Several Antibiotics

J Int Med Res. 2008 Jan-Feb

Wu CM, Cao JL, Zheng MH, Ou Y, Zhang L, Zhu XQ, Song JX.Department of Liver Diseases, The Traditional Chinese Medical Hospital of Wenzhou, Wenzhou, China.

Effectiveness and mechanism of action of andrographolide on the recovery of Pseudomonas aeruginosa susceptibility to antibiotics was investigated. In the presence of andrographolide, the Mueller-Hinton broth dilution method measured minimal inhibitory concentrations (MIC) of ceftazidine, cefpirome, chloramphenicol, L-ofloxacin, kanamycin, imipenem and meropenem. Real-time fluorescence quantitative polymerase chain reaction was used to determine mexB mRNA expressions in P. aeruginosa PAO1 strain and MexAB-OprM overexpressing strain. Relative mexB mRNA expression was detected in both strains incubated for 3 and 9 h. When andrographolide-treated groups were compared with controls, the MIC of ceftazidine, cefpirome, L-ofloxacin and meropenem for both strains decreased, and the relative mexB mRNA expression was significantly lower, although between andrographolide groups there were no significant differences. Compared with the inactivated quorum-sensing system, relative amounts of mexB mRNA in the PAO1 strain and MexAB-OprM overexpressing strain in the activated quorum-sensing system increased 10- and 30-fold, respectively. Andrographolide recovered P. aeruginosa susceptibility to antibiotics and reduced the MexAB-OprM efflux pump expression level.

PMID: 18304418 [PubMed - in process]